<!doctype html><html lang="en">
 <head>
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  <meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
  <title>P3540R2: #embed offset parameter</title>
<style data-fill-with="stylesheet">/******************************************************************************
 *                   Style sheet for the W3C specifications                   *
 *
 * Special classes handled by this style sheet include:
 *
 * Indices
 *   - .toc for the Table of Contents (<ol class="toc">)
 *     + <span class="secno"> for the section numbers
 *   - #toc for the Table of Contents (<nav id="toc">)
 *   - ul.index for Indices (<a href="#ref">term</a><span>, in § N.M</span>)
 *   - table.index for Index Tables (e.g. for properties or elements)
 *
 * Structural Markup
 *   - table.data for general data tables
 *     -> use 'scope' attribute, <colgroup>, <thead>, and <tbody> for best results !
 *     -> use <table class='complex data'> for extra-complex tables
 *     -> use <td class='long'> for paragraph-length cell content
 *     -> use <td class='pre'> when manual line breaks/indentation would help readability
 *   - dl.switch for switch statements
 *   - ol.algorithm for algorithms (helps to visualize nesting)
 *   - .figure and .caption (HTML4) and figure and figcaption (HTML5)
 *     -> .sidefigure for right-floated figures
 *   - ins/del
 *     -> ins/del.c### for candidate and proposed changes (amendments)
 *
 * Code
 *   - pre and code
 *
 * Special Sections
 *   - .note       for informative notes             (div, p, span, aside, details)
 *   - .example    for informative examples          (div, p, pre, span)
 *   - .issue      for issues                        (div, p, span)
 *   - .advisement for loud normative statements     (div, p, strong)
 *   - .annoying-warning for spec obsoletion notices (div, aside, details)
 *   - .correction for "candidate corrections"       (div, aside, details, section)
 *   - .addition   for "candidate additions"         (div, aside, details, section)
 *   - .correction.proposed for "proposed corrections" (div, aside, details, section)
 *   - .addition.proposed   for "proposed additions"   (div, aside, details, section)
 *
 * Definition Boxes
 *   - pre.def   for WebIDL definitions
 *   - table.def for tables that define other entities (e.g. CSS properties)
 *   - dl.def    for definition lists that define other entitles (e.g. HTML elements)
 *
 * Numbering
 *   - .secno for section numbers in .toc and headings (<span class='secno'>3.2</span>)
 *   - .marker for source-inserted example/figure/issue numbers (<span class='marker'>Issue 4</span>)
 *   - ::before styled for CSS-generated issue/example/figure numbers:
 *     -> Documents wishing to use this only need to add
 *        figcaption::before,
 *        .caption::before { content: "Figure "  counter(figure) " ";  }
 *        .example::before { content: "Example " counter(example) " "; }
 *        .issue::before   { content: "Issue "   counter(issue) " ";   }
 *
 * Header Stuff (ignore, just don't conflict with these classes)
 *   - .head for the header
 *   - .copyright for the copyright
 *
 * Outdated warning for old specs
 *
 * Miscellaneous
 *   - .overlarge for things that should be as wide as possible, even if
 *     that overflows the body text area. This can be used on an item or
 *     on its container, depending on the effect desired.
 *     Note that this styling basically doesn't help at all when printing,
 *     since A4 paper isn't much wider than the max-width here.
 *     It's better to design things to fit into a narrower measure if possible.
 *
 *   - js-added ToC jump links (see fixup.js)
 *
 ******************************************************************************/

/* color variables included separately for reliability */

/******************************************************************************/
/*                                    Body                                    */
/******************************************************************************/

	html {
	}

	body {
		counter-reset: example figure issue;

		/* Layout */
		max-width: 50em;			  /* limit line length to 50em for readability   */
		margin: 0 auto;				/* center text within page                    */
		padding: 1.6em 1.5em 2em 50px; /* assume 16px font size for downlevel clients */
		padding: 1.6em 1.5em 2em calc(26px + 1.5em); /* leave space for status flag    */

		/* Typography */
		line-height: 1.5;
		font-family: sans-serif;
		widows: 2;
		orphans: 2;
		word-wrap: break-word;
		overflow-wrap: break-word;
		hyphens: auto;

		color: black;
		color: var(--text);
		background: white top left fixed no-repeat;
		background: var(--bg) top left fixed no-repeat;
		background-size: 25px auto;
	}


/******************************************************************************/
/*                         Front Matter & Navigation                          */
/******************************************************************************/

/** Header ********************************************************************/

	div.head { margin-bottom: 1em; }
	div.head hr { border-style: solid; }

	div.head h1 {
		font-weight: bold;
		margin: 0 0 .1em;
		font-size: 220%;
	}

	div.head h2 { margin-bottom: 1.5em;}

/** W3C Logo ******************************************************************/

	.head .logo {
		float: right;
		margin: 0.4rem 0 0.2rem .4rem;
	}

	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border: solid var(--logo-bg);
		border-width: .65rem .7rem .6rem;
		border-radius: .4rem;
		background: #1a5e9a;
		background: var(--logo-bg);
		color: white;
		color: var(--logo-text);
		font-weight: bold;
	}

	.head a:hover > img[src*="logos/W3C"],
	.head a:focus > img[src*="logos/W3C"] {
		opacity: .8;
	}

	.head a:active > img[src*="logos/W3C"] {
		background: #c00;
		background: var(--logo-active-bg);
		border-color: #c00;
		border-color: var(--logo-active-bg);
	}

	/* see also additional rules in Link Styling section */

/** Copyright *****************************************************************/

	p.copyright,
	p.copyright small { font-size: small; }

/** Back to Top / ToC Toggle **************************************************/

	@media print {
		#toc-nav {
			display: none;
		}
	}
	@media not print {
		#toc-nav {
			position: fixed;
			z-index: 3;
			bottom: 0; left: 0;
			margin: 0;
			min-width: 1.33em;
			border-top-right-radius: 2rem;
			box-shadow: 0 0 2px;
			font-size: 1.5em;
		}
		#toc-nav > a {
			display: block;
			white-space: nowrap;

			height: 1.33em;
			padding: .1em 0.3em;
			margin: 0;

			box-shadow: 0 0 2px;
			border: none;
			border-top-right-radius: 1.33em;

			color: #707070;
			color: var(--tocnav-normal-text);
			background: white;
			background: var(--tocnav-normal-bg);
		}
		#toc-nav > a:hover,
		#toc-nav > a:focus {
			color: black;
			color: var(--tocnav-hover-text);
			background: #f8f8f8;
			background: var(--tocnav-hover-bg);
		}
		#toc-nav > a:active {
			color: #c00;
			color: var(--tocnav-active-text);
			background: white;
			background: var(--tocnav-active-bg);
		}

		#toc-nav > #toc-jump {
			padding-bottom: 2em;
			margin-bottom: -1.9em;
		}

		/* statusbar gets in the way on keyboard focus; remove once browsers fix */
		#toc-nav > a[href="#toc"]:not(:hover):focus:last-child {
			padding-bottom: 1.5rem;
		}

		#toc-nav:not(:hover) > a:not(:focus) > span + span {
			/* Ideally this uses :focus-within on #toc-nav */
			display: none;
		}
		#toc-nav > a > span + span {
			padding-right: 0.2em;
		}
	}

/** ToC Sidebar ***************************************************************/

	/* Floating sidebar */
	@media screen {
		body.toc-sidebar #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			max-width: 80%;
			max-width: calc(100% - 2em - 26px);
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			color: black;
			color: var(--tocsidebar-text);
			background: inherit;
			background-color: #f7f8f9;
			background-color: var(--tocsidebar-bg);
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
			box-shadow: -.1em 0 .25em var(--tocsidebar-shadow) inset;
		}
		body.toc-sidebar #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
			color: var(--tocsidebar-heading-text);
		}
		body.toc-sidebar #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	/* Hide main scroller when only the ToC is visible anyway */
	@media screen and (max-width: 28em) {
		body.toc-sidebar {
			overflow: hidden;
		}
	}

	/* Sidebar with its own space */
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			color: black;
			color: var(--tocsidebar-text);
			background: inherit;
			background-color: #f7f8f9;
			background-color: var(--tocsidebar-bg);
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
			box-shadow: -.1em 0 .25em var(--tocsidebar-shadow) inset;
		}
		body:not(.toc-inline) #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
			color: var(--tocsidebar-heading-text);
		}

		body:not(.toc-inline) {
			padding-left: 29em;
		}
		/* See also Overflow section at the bottom */

		body:not(.toc-inline) #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) {
			margin: 0 4em;
		}
	}

/******************************************************************************/
/*                                Sectioning                                  */
/******************************************************************************/

/** Headings ******************************************************************/

	h1, h2, h3, h4, h5, h6, dt {
		page-break-after: avoid;
		page-break-inside: avoid;
		font: 100% sans-serif;   /* Reset all font styling to clear out UA styles */
		font-family: inherit;	/* Inherit the font family. */
		line-height: 1.2;		/* Keep wrapped headings compact */
		hyphens: manual;		/* Hyphenated headings look weird */
	}

	h2, h3, h4, h5, h6 {
		margin-top: 3rem;
	}

	h1, h2, h3 {
		color: #005A9C;
		color: var(--heading-text);
	}

	h1 { font-size: 170%; }
	h2 { font-size: 140%; }
	h3 { font-size: 120%; }
	h4 { font-weight: bold; }
	h5 { font-style: italic; }
	h6 { font-variant: small-caps; }
	dt { font-weight: bold; }

/** Subheadings ***************************************************************/

	h1 + h2,
	#profile-and-date {
		/* #profile-and-date is a subtitle in an H2 under the H1 */
		margin-top: 0;
	}
	h2 + h3,
	h3 + h4,
	h4 + h5,
	h5 + h6 {
		margin-top: 1.2em; /* = 1 x line-height */
	}

/** Section divider ***********************************************************/

	:not(.head) > :not(.head) + hr {
		font-size: 1.5em;
		text-align: center;
		margin: 1em auto;
		height: auto;
		color: black;
		color: var(--hr-text);
		border: transparent solid 0;
		background: transparent;
	}
	:not(.head) > hr::before {
		content: "\2727\2003\2003\2727\2003\2003\2727";
	}

/******************************************************************************/
/*                            Paragraphs and Lists                            */
/******************************************************************************/

	p {
		margin: 1em 0;
	}

	dd > p:first-child,
	li > p:first-child {
		margin-top: 0;
	}

	ul, ol {
		margin-left: 0;
		padding-left: 2em;
	}

	li {
		margin: 0.25em 0 0.5em;
		padding: 0;
	}

	dl dd {
		margin: 0 0 .5em 2em;
	}

	.head dd + dd { /* compact for header */
		margin-top: -.5em;
	}

	/* Style for algorithms */
	ol.algorithm ol:not(.algorithm),
	.algorithm > ol ol:not(.algorithm) {
	border-left: 0.5em solid #DEF;
	border-left: 0.5em solid var(--algo-border);
	}

	/* Put nice boxes around each algorithm. */
	[data-algorithm]:not(.heading) {
	 padding: .5em;
	 border: thin solid #ddd;
	 border: thin solid var(--algo-border);
	 border-radius: .5em;
	 margin: .5em calc(-0.5em - 1px);
	}
	[data-algorithm]:not(.heading) > :first-child {
	 margin-top: 0;
	}
	[data-algorithm]:not(.heading) > :last-child {
	 margin-bottom: 0;
	}

	/* Style for switch/case <dl>s */
	dl.switch > dd > ol.only,
	dl.switch > dd > .only > ol {
	margin-left: 0;
	}
	dl.switch > dd > ol.algorithm,
	dl.switch > dd > .algorithm > ol {
	margin-left: -2em;
	}
	dl.switch {
	padding-left: 2em;
	}
	dl.switch > dt {
	text-indent: -1.5em;
	margin-top: 1em;
	}
	dl.switch > dt + dt {
	margin-top: 0;
	}
	dl.switch > dt::before {
	content: '\21AA';
	padding: 0 0.5em 0 0;
	display: inline-block;
	width: 1em;
	text-align: right;
	line-height: 0.5em;
	}

/** Terminology Markup ********************************************************/


/******************************************************************************/
/*                                 Inline Markup                              */
/******************************************************************************/

/** Terminology Markup ********************************************************/
	dfn   { /* Defining instance */
		font-weight: bolder;
	}
	a > i { /* Instance of term */
		font-style: normal;
	}
	dt dfn code, code.idl {
		font-size: inherit;
	}
	dfn var {
		font-style: normal;
	}

/** Change Marking ************************************************************/

	del {
		color: #aa0000;
		color: var(--del-text);
		background: transparent;
		background: var(--del-bg);
		text-decoration: line-through;
	}
	ins {
		color: #006100;
		color: var(--ins-text);
		background: transparent;
		background: var(--ins-bg);
		text-decoration: underline;
	}

	/* for amendments (candidate/proposed changes) */

	.amendment ins, .correction ins, .addition ins,
	ins[class^=c] {
		text-decoration-style: dotted;
	}
	.amendment del, .correction del, .addition del,
	del[class^=c] {
		text-decoration-style: dotted;
	}
	.amendment.proposed ins, .correction.proposed ins, .addition.proposed ins,
	ins[class^=c].proposed {
		text-decoration-style: double;
	}
	.amendment.proposed del, .correction.proposed del, .addition.proposed del,
	del[class^=c].proposed {
		text-decoration-style: double;
	}

/** Miscellaneous improvements to inline formatting ***************************/

	sup {
		vertical-align: super;
		font-size: 80%
	}

/******************************************************************************/
/*                                    Code                                    */
/******************************************************************************/

/** General monospace/pre rules ***********************************************/

	pre, code, samp {
		font-family: Menlo, Consolas, "DejaVu Sans Mono", Monaco, monospace;
		font-size: .9em;
		hyphens: none;
		text-transform: none;
		text-align: left;
		text-align: start;
		font-variant: normal;
		orphans: 3;
		widows: 3;
		page-break-before: avoid;
	}
	pre code,
	code code {
		font-size: 100%;
	}

	pre {
		margin-top: 1em;
		margin-bottom: 1em;
		overflow: auto;
	}

/** Inline Code fragments *****************************************************/

	/* Do something nice. */

/******************************************************************************/
/*                                    Links                                   */
/******************************************************************************/

/** General Hyperlinks ********************************************************/

	/* We hyperlink a lot, so make it less intrusive */
	a[href] {
		color: #034575;
		color: var(--a-normal-text);
		text-decoration: underline #707070;
		text-decoration: underline var(--a-normal-underline);
		text-decoration-skip-ink: none;
	}
	a:visited {
		color: #034575;
		color: var(--a-visited-text);
		text-decoration-color: #bbb;
		text-decoration-color: var(--a-visited-underline);
	}

	/* Indicate interaction with the link */
	a[href]:focus,
	a[href]:hover {
		text-decoration-thickness: 2px;
	}
	a[href]:active {
		color: #c00;
		color: var(--a-active-text);
		text-decoration-color: #c00;
		text-decoration-color: var(--a-active-underline);
	}

	/* Backout above styling for W3C logo */
	.head .logo,
	.head .logo a {
		border: none;
		text-decoration: none;
		background: transparent;
	}

/******************************************************************************/
/*                                    Images                                  */
/******************************************************************************/

	img {
		border-style: none;
	}

	img, svg {
		/* Intentionally not color-scheme aware. */
		background: white;
	}

	/* For autogen numbers, add
	  .caption::before, figcaption::before { content: "Figure " counter(figure) ". "; }
	*/

	figure, .figure, .sidefigure {
		page-break-inside: avoid;
		text-align: center;
		margin: 2.5em 0;
	}
	.figure img,	.sidefigure img,	figure img,
	.figure object, .sidefigure object, figure object {
		max-width: 100%;
		margin: auto;
		height: auto;
	}
	.figure pre, .sidefigure pre, figure pre {
		text-align: left;
		display: table;
		margin: 1em auto;
	}
	.figure table, figure table {
		margin: auto;
	}
	@media screen and (min-width: 20em) {
		.sidefigure {
			float: right;
			width: 50%;
			margin: 0 0 0.5em 0.5em;
		}
	}
	.caption, figcaption, caption {
		font-style: italic;
		font-size: 90%;
	}
	.caption::before, figcaption::before, figcaption > .marker {
		font-weight: bold;
	}
	.caption, figcaption {
		counter-increment: figure;
	}

	/* DL list is indented 2em, but figure inside it is not */
	dd > .figure, dd > figure { margin-left: -2em; }

/******************************************************************************/
/*                             Colored Boxes                                  */
/******************************************************************************/

	.issue, .note, .example, .assertion, .advisement, blockquote,
	.amendment, .correction, .addition {
		margin: 1em auto;
		padding: .5em;
		border: .5em;
		border-left-style: solid;
		page-break-inside: avoid;
	}
	span.issue, span.note {
		padding: .1em .5em .15em;
		border-right-style: solid;
	}

	blockquote > :first-child,
	.note  > p:first-child,
	.issue > p:first-child,
	.amendment > p:first-child,
	.correction > p:first-child,
	.addition > p:first-child {
		margin-top: 0;
	}
	blockquote > :last-child,
	.note  > p:last-child,
	.issue > p:last-child,
	.amendment > p:last-child,
	.correction > p:last-child,
	.addition > p:last-child {
		margin-bottom: 0;
	}


	.issue::before, .issue > .marker,
	.example::before, .example > .marker,
	.note::before, .note > .marker,
	details.note > summary > .marker,
	.amendment::before, .amendment > .marker,
	details.amendment > summary > .marker,
	.addition::before, .addition > .marker,
	addition.amendment > summary > .marker,
	.correction::before, .correction > .marker,
	correction.amendment > summary > .marker
	{
		text-transform: uppercase;
		padding-right: 1em;
	}

	.example::before, .example > .marker {
		display: block;
		padding-right: 0em;
	}

/** Blockquotes ***************************************************************/

	blockquote {
		border-color: silver;
		border-color: var(--blockquote-border);
		background: transparent;
		background: var(--blockquote-bg);
		color: currentcolor;
		color: var(--blockquote-text);
	}

/** Open issue ****************************************************************/

	.issue {
		border-color: #e05252;
		border-color: var(--issue-border);
		background: #fbe9e9;
		background: var(--issue-bg);
		color: black;
		color: var(--issue-text);
		counter-increment: issue;
		overflow: auto;
	}
	.issue::before, .issue > .marker {
		color: #831616;
		color: var(--issueheading-text);
	}
	/* Add .issue::before { content: "Issue " counter(issue) " "; } for autogen numbers,
	  or use class="marker" to mark up the issue number in source. */

/** Example *******************************************************************/

	.example {
		border-color: #e0cb52;
		border-color: var(--example-border);
		background: #fcfaee;
		background: var(--example-bg);
		color: black;
		color: var(--example-text);
		counter-increment: example;
		overflow: auto;
		clear: both;
	}
	.example::before, .example > .marker {
		color: #574b0f;
		color: var(--exampleheading-text);
	}
	/* Add .example::before { content: "Example " counter(example) " "; } for autogen numbers,
	  or use class="marker" to mark up the example number in source. */

/** Non-normative Note ********************************************************/

	.note {
		border-color: #52e052;
		border-color: var(--note-border);
		background: #e9fbe9;
		background: var(--note-bg);
		color: black;
		color: var(--note-text);
		overflow: auto;
	}

	.note::before, .note > .marker,
	details.note > summary {
		color: hsl(120, 70%, 30%);
		color: var(--noteheading-text);
	}
	/* Add .note::before { content: "Note "; } for autogen label,
	  or use class="marker" to mark up the label in source. */

	details.note[open] > summary {
		border-bottom: 1px silver solid;
		border-bottom: 1px var(--notesummary-underline) solid;
	}

/** Assertion Box *************************************************************/
	/*  for assertions in algorithms */

	.assertion {
		border-color: #AAA;
		border-color: var(--assertion-border);
		background: #EEE;
		background: var(--assertion-bg);
		color: black;
		color: var(--assertion-text);
	}

/** Advisement Box ************************************************************/
	/*  for attention-grabbing normative statements */

	.advisement {
		border-color: orange;
		border-color: var(--advisement-border);
		border-style: none solid;
		background: #fec;
		background: var(--advisement-bg);
		color: black;
		color: var(--advisement-text);
	}
	strong.advisement {
		display: block;
		text-align: center;
	}
	.advisement::before, .advisement > .marker {
		color: #b35f00;
		color: var(--advisementheading-text);
	}

/** Amendment Box *************************************************************/

	.amendment, .correction, .addition {
		border-color: #330099;
		border-color: var(--amendment-border);
		background: #F5F0FF;
		background: var(--amendment-bg);
		color: black;
		color: var(--amendment-text);
	}
	.amendment.proposed, .correction.proposed, .addition.proposed {
		border-style: solid;
		border-block-width: 0.25em;
	}
	.amendment::before, .amendment > .marker,
	details.amendment > summary::before, details.amendment > summary > .marker,
	.correction::before, .correction > .marker,
	details.correction > summary::before, details.correction > summary > .marker,
	.addition::before, .addition > .marker,
	details.addition > summary::before, details.addition > summary > .marker {
		color: #220066;
		color: var(--amendmentheading-text);
	}
	.amendment.proposed::before, .amendment.proposed > .marker,
	details.amendment.proposed > summary::before, details.amendment.proposed > summary > .marker,
	.correction.proposed::before, .correction.proposed > .marker,
	details.correction.proposed > summary::before, details.correction.proposed > summary > .marker,
	.addition.proposed::before, .addition.proposed > .marker,
	details.addition.proposed > summary::before, details.addition.proposed > summary > .marker {
		font-weight: bold;
	}

/** Spec Obsoletion Notice ****************************************************/
	/* obnoxious obsoletion notice for older/abandoned specs. */

	details {
		display: block;
	}
	summary {
		font-weight: bolder;
	}

	.annoying-warning:not(details),
	details.annoying-warning:not([open]) > summary,
	details.annoying-warning[open] {
		background: hsla(40,100%,50%,0.95);
		background: var(--warning-bg);
		color: black;
		color: var(--warning-text);
		padding: .75em 1em;
		border: red;
		border: var(--warning-border);
		border-style: solid none;
		box-shadow: 0 2px 8px black;
		text-align: center;
	}
	.annoying-warning :last-child {
		margin-bottom: 0;
	}

@media not print {
	details.annoying-warning[open] {
		position: fixed;
		left: 0;
		right: 0;
		bottom: 2em;
		z-index: 1000;
	}
}

	details.annoying-warning:not([open]) > summary {
		text-align: center;
	}

/** Entity Definition Boxes ***************************************************/

	.def {
		padding: .5em 1em;
		background: #def;
		background: var(--def-bg);
		margin: 1.2em 0;
		border-left: 0.5em solid #8ccbf2;
		border-left: 0.5em solid var(--def-border);
		color: black;
		color: var(--def-text);
	}

/******************************************************************************/
/*                                    Tables                                  */
/******************************************************************************/

	th, td {
		text-align: left;
		text-align: start;
	}

/** Property/Descriptor Definition Tables *************************************/

	table.def {
		/* inherits .def box styling, see above */
		width: 100%;
		border-spacing: 0;
	}

	table.def td,
	table.def th {
		padding: 0.5em;
		vertical-align: baseline;
		border-bottom: 1px solid #bbd7e9;
		border-bottom: 1px solid var(--defrow-border);
	}

	table.def > tbody > tr:last-child th,
	table.def > tbody > tr:last-child td {
		border-bottom: 0;
	}

	table.def th {
		font-style: italic;
		font-weight: normal;
		padding-left: 1em;
		width: 3em;
	}

	/* For when values are extra-complex and need formatting for readability */
	table td.pre {
		white-space: pre-wrap;
	}

	/* A footnote at the bottom of a def table */
	table.def td.footnote {
		padding-top: 0.6em;
	}
	table.def td.footnote::before {
		content: " ";
		display: block;
		height: 0.6em;
		width: 4em;
		border-top: thin solid;
	}

/** Data tables (and properly marked-up index tables) *************************/
	/*
		<table class="data"> highlights structural relationships in a table
		when correct markup is used (e.g. thead/tbody, th vs. td, scope attribute)

		Use class="complex data" for particularly complicated tables --
		(This will draw more lines: busier, but clearer.)

		Use class="long" on table cells with paragraph-like contents
		(This will adjust text alignment accordingly.)
		Alternately use class="longlastcol" on tables, to have the last column assume "long".
	*/

	table {
		word-wrap: normal;
		overflow-wrap: normal;
		hyphens: manual;
	}

	table.data,
	table.index {
		margin: 1em auto;
		border-collapse: collapse;
		border: hidden;
		width: 100%;
	}
	table.data caption,
	table.index caption {
		max-width: 50em;
		margin: 0 auto 1em;
	}

	table.data td,  table.data th,
	table.index td, table.index th {
		padding: 0.5em 1em;
		border-width: 1px;
		border-color: silver;
		border-color: var(--datacell-border);
		border-top-style: solid;
	}

	table.data thead td:empty {
		padding: 0;
		border: 0;
	}

	table.data  thead,
	table.index thead,
	table.data  tbody,
	table.index tbody {
		border-bottom: 2px solid;
	}

	table.data colgroup,
	table.index colgroup {
		border-left: 2px solid;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		border-right: 2px solid;
		border-top: 1px solid silver;
		border-top: 1px solid var(--datacell-border);
		padding-right: 1em;
	}

	table.data th[colspan],
	table.data td[colspan] {
		text-align: center;
	}

	table.complex.data th,
	table.complex.data td {
		border: 1px solid silver;
		border: 1px solid var(--datacell-border);
		text-align: center;
	}

	table.data.longlastcol td:last-child,
	table.data td.long {
		vertical-align: baseline;
		text-align: left;
	}

	table.data img {
		vertical-align: middle;
	}


/*
Alternate table alignment rules

	table.data,
	table.index {
		text-align: center;
	}

	table.data  thead th[scope="row"],
	table.index thead th[scope="row"] {
		text-align: right;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		text-align: right;
	}

Possible extra rowspan handling

	table.data  tbody th[rowspan]:not([rowspan='1']),
	table.index tbody th[rowspan]:not([rowspan='1']),
	table.data  tbody td[rowspan]:not([rowspan='1']),
	table.index tbody td[rowspan]:not([rowspan='1']) {
		border-left: 1px solid silver;
	}

	table.data  tbody th[rowspan]:first-child,
	table.index tbody th[rowspan]:first-child,
	table.data  tbody td[rowspan]:first-child,
	table.index tbody td[rowspan]:first-child{
		border-left: 0;
		border-right: 1px solid silver;
	}
*/

/******************************************************************************/
/*                                  Indices                                   */
/******************************************************************************/


/** Table of Contents *********************************************************/

	.toc a {
		/* More spacing; use padding to make it part of the click target. */
		padding: 0.1rem 1px 0;
		/* Larger, more consistently-sized click target */
		display: block;
		/* Switch to using border-bottom for underlines */
		text-decoration: none;
		border-bottom: 1px solid;
		/* Reverse color scheme */
		color: black;
		color: var(--toclink-text);
		border-color: #3980b5;
		border-color: var(--toclink-underline);
	}
	.toc a:visited {
		color: black;
		color: var(--toclink-visited-text);
		border-color: #054572;
		border-color: var(--toclink-visited-underline);
	}
	.toc a:focus,
	.toc a:hover {
		background: rgba(75%, 75%, 75%, .25);
		background: var(--a-hover-bg);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	.toc a:not(:focus):not(:hover) {
		/* Allow colors to cascade through from link styling */
		border-bottom-color: transparent;
	}

	.toc, .toc ol, .toc ul, .toc li {
		list-style: none; /* Numbers must be inlined into source */
		/* because generated content isn't search/selectable and markers can't do multilevel yet */
		margin:  0;
		padding: 0;
	}
	.toc {
		line-height: 1.1em;
	}

	/* ToC not indented until third level, but font style & margins show hierarchy */
	.toc > li			{ font-weight: bold;   }
	.toc > li li		 { font-weight: normal; }
	.toc > li li li	  { font-size:   95%;	}
	.toc > li li li li	{ font-size:   90%;	}
	.toc > li li li li li { font-size:   85%;	}

	/* @supports not (display:grid) { */
		.toc > li			{ margin: 1.5rem 0;	}
		.toc > li li		 { margin: 0.3rem 0;	}
		.toc > li li li	  { margin-left: 2rem;   }

		/* Section numbers in a column of their own */
		.toc .secno {
			float: left;
			width: 4rem;
			white-space: nowrap;
		}
		.toc > li li li li .secno { font-size: 85%; }
		.toc > li li li li li .secno { font-size: 100%; }

		.toc li {
			clear: both;
		}

		:not(li) > .toc			 { margin-left:  5rem; }
		.toc .secno				 { margin-left: -5rem; }
		.toc > li li li .secno	  { margin-left: -7rem; }
		.toc > li li li li .secno	{ margin-left: -9rem; }
		.toc > li li li li li .secno { margin-left: -11rem; }

		/* Tighten up indentation in narrow ToCs */
		@media (max-width: 30em) {
			:not(li) > .toc			 { margin-left:  4rem; }
			.toc .secno				 { margin-left: -4rem; }
			.toc > li li li			 { margin-left:  1rem; }
			.toc > li li li .secno	  { margin-left: -5rem; }
			.toc > li li li li .secno	{ margin-left: -6rem; }
			.toc > li li li li li .secno { margin-left: -7rem; }
		}
		/* Loosen it on wide screens */
		@media screen and (min-width: 78em) {
			body:not(.toc-inline) :not(li) > .toc			 { margin-left:  4rem; }
			body:not(.toc-inline) .toc .secno				 { margin-left: -4rem; }
			body:not(.toc-inline) .toc > li li li			 { margin-left:  1rem; }
			body:not(.toc-inline) .toc > li li li .secno	  { margin-left: -5rem; }
			body:not(.toc-inline) .toc > li li li li .secno	{ margin-left: -6rem; }
			body:not(.toc-inline) .toc > li li li li li .secno { margin-left: -7rem; }
	}
	/* } */

	@supports (display:grid) and (display:contents) {
		/* Use #toc over .toc to override non-@supports rules. */
		#toc {
			display: grid;
			align-content: start;
			grid-template-columns: auto 1fr;
			grid-column-gap: 1rem;
			column-gap: 1rem;
			grid-row-gap: .6rem;
			row-gap: .6rem;
		}
		#toc h2 {
			grid-column: 1 / -1;
			margin-bottom: 0;
		}
		#toc ol,
		#toc li,
		#toc a {
			display: contents;
			/* Switch <a> to subgrid when supported */
		}
		#toc span {
			margin: 0;
		}
		#toc > .toc > li > a > span {
			/* The spans of the top-level list,
			  comprising the first items of each top-level section. */
			margin-top: 1.1rem;
		}
		#toc#toc .secno { /* Ugh, need more specificity to override base.css */
			grid-column: 1;
			width: auto;
			margin-left: 0;
		}
		#toc .content {
			grid-column: 2;
			width: auto;
			margin-right: 1rem;
			border-bottom: 3px solid transparent;
			margin-bottom: -3px;
		}
		#toc .content:hover,
		#toc .content:focus {
			background: rgba(75%, 75%, 75%, .25);
			background: var(--a-hover-bg);
			border-bottom-color: #054572;
			border-bottom-color: var(--toclink-underline);
		}
		#toc li li li .content {
			margin-left: 1rem;
		}
		#toc li li li li .content {
			margin-left: 2rem;
		}
	}


/** Index *********************************************************************/

	/* Index Lists: Layout */
	ul.index	  { margin-left: 0; columns: 15em; text-indent: 1em hanging; }
	ul.index li	{ margin-left: 0; list-style: none; break-inside: avoid; }
	ul.index li li { margin-left: 1em; }
	ul.index dl	{ margin-top: 0; }
	ul.index dt	{ margin: .2em 0 .2em 20px;}
	ul.index dd	{ margin: .2em 0 .2em 40px;}
	/* Index Lists: Typography */
	ul.index ul,
	ul.index dl { font-size: smaller; }
	@media not print {
		ul.index li a + span {
			white-space: nowrap;
			color: transparent; }
		ul.index li a:hover + span,
		ul.index li a:focus + span {
			color: #707070;
			color: var(--indexinfo-text);
		}
	}

/** Index Tables *****************************************************/
	/* See also the data table styling section, which this effectively subclasses */

	table.index {
		font-size: small;
		border-collapse: collapse;
		border-spacing: 0;
		text-align: left;
		margin: 1em 0;
	}

	table.index td,
	table.index th {
		padding: 0.4em;
	}

	table.index tr:hover td:not([rowspan]),
	table.index tr:hover th:not([rowspan]) {
		color: black;
		color: var(--indextable-hover-text);
		background: #f7f8f9;
		background: var(--indextable-hover-bg);
	}

	/* The link in the first column in the property table (formerly a TD) */
	table.index th:first-child a {
		font-weight: bold;
	}

/** Outdated warning **********************************************************/

.outdated-spec {
	color: black;
	color: var(--outdatedspec-text);
	background-color: rgba(0,0,0,0.5);
	background-color: var(--outdatedspec-bg);
}

.outdated-warning {
	position: fixed;
	bottom: 50%;
	left: 0;
	right: 0;
	margin: 0 auto;
	width: 50%;
	background: maroon;
	background: var(--outdated-bg);
	color: white;
	color: var(--outdated-text);
	border-radius: 1em;
	box-shadow: 0 0 1em red;
	box-shadow: 0 0 1em var(--outdated-shadow);
	padding: 2em;
	text-align: center;
	z-index: 2;
}

.outdated-warning a {
	color: currentcolor;
	background: transparent;
}

.edited-rec-warning {
	background: darkorange;
	background: var(--editedrec-bg);
	box-shadow: 0 0 1em;
}

.outdated-warning button {
	color: var(--outdated-text);
	border-radius: 1em;
	box-shadow: 0 0 1em red;
	box-shadow: 0 0 1em var(--outdated-shadow);
	padding: 2em;
	text-align: center;
	z-index: 2;
}

.outdated-warning a {
	color: currentcolor;
	background: transparent;
}

.edited-rec-warning {
	background: darkorange;
	background: var(--editedrec-bg);
	box-shadow: 0 0 1em;
}

.outdated-warning button {
	position: absolute;
	top: 0;
	right:0;
	margin: 0;
	border: 0;
	padding: 0.25em 0.5em;
	background: transparent;
	color: white;
	color: var(--outdated-text);
	font:1em sans-serif;
	text-align:center;
}

.outdated-warning span {
	display: block;
}

.outdated-collapsed {
	bottom: 0;
	border-radius: 0;
	width: 100%;
	padding: 0;
}

/******************************************************************************/
/*                                    Print                                   */
/******************************************************************************/

	@media print {
		/* Pages have their own margins. */
		html {
			margin: 0;
		}
		/* Serif for print. */
		body {
			font-family: serif;
		}

		.outdated-warning {
			position: absolute;
			border-style: solid;
			border-color: red;
		}

		.outdated-warning input {
			display: none;
		}
	}
	@page {
		margin: 1.5cm 1.1cm;
	}



/******************************************************************************/
/*                             Overflow Control                               */
/******************************************************************************/

	.figure .caption, .sidefigure .caption, figcaption {
		/* in case figure is overlarge, limit caption to 50em */
		max-width: 50rem;
		margin-left: auto;
		margin-right: auto;
	}
	.overlarge {
		/* Magic to create good item positioning:
		  "content column" is 50ems wide at max; less on smaller screens.
		  Extra space (after ToC + content) is empty on the right.

		  1. When item < content column, centers item in column.
		  2. When content < item < available, left-aligns.
		  3. When item > available, fills available + scroll bar.
		*/
		display: grid;
		grid-template-columns: minmax(0, 50em);
	}
	.overlarge > table {
		/* limit preferred width of table */
		max-width: 50em;
		margin-left: auto;
		margin-right: auto;
	}

	@media (min-width: 55em) {
		.overlarge {
			margin-right: calc(13px + 26.5rem - 50vw);
			max-width: none;
		}
	}
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) .overlarge {
			/* 30.5em body padding 50em content area */
			margin-right: calc(40em - 50vw) !important;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) .overlarge {
			/* 4em html margin 30.5em body padding 50em content area */
			margin-right: calc(84.5em - 100vw) !important;
		}
	}

	@media not print {
		.overlarge {
			overflow-x: auto;
			/* See Lea Verou's explanation background-attachment:
			* http://lea.verou.me/2012/04/background-attachment-local/
			*
			background: top left  / 4em 100% linear-gradient(to right,  #ffffff, rgba(255, 255, 255, 0)) local,
						top right / 4em 100% linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0)) local,
						top left  / 1em 100% linear-gradient(to right,  #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						top right / 1em 100% linear-gradient(to left, #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						white;
			background-repeat: no-repeat;
			*/
		}
	}
</style>
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    }
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    del { background: #fcc; color: #000; text-decoration: line-through; }
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:root {
	/* Default (light) theme */
	--foreground-point: rgb(0,0,0);
	--background-point: rgb(255,255,255);

	--ins-text-color: rgb(0, 182, 15);
	--diff-ins-text-color: rgb(0, 176, 189);
	--del-text-color: rgb(255, 58, 58);
	--diff-del-text-color: rgb(139, 0, 194);
}

/* dark theme */
@media (prefers-color-scheme: dark) {
	:root {
		--foreground-point: rgb(255,255,255);
		--background-point: rgb(0,0,0);

		--ins-text-color: rgb(48, 255, 48);
		--diff-ins-text-color: rgb(91, 250, 255);
		--del-text-color: rgb(255, 52, 52);
		--diff-del-text-color: rgb(244, 129, 255);
	}
}

:root {
	--ins-text-background-color: color-mix(in srgb, var(--ins-text-color) 5%, var(--background-point));
	--ins-code-background-color: color-mix(in srgb, var(--ins-text-color) 15%, var(--background-point));
	--ins-text-decoration-color: color-mix(in srgb, var(--ins-text-color) 10%, var(--foreground-point));
	--ins-text-border-color: color-mix(in srgb, var(--ins-text-color) 50%, var(--foreground-point));
	--diff-ins-text-background-color: color-mix(in srgb, var(--diff-ins-text-color) 5%, var(--background-point));
	--diff-ins-code-background-color: color-mix(in srgb, var(--diff-ins-text-color) 15%, var(--background-point));
	--diff-ins-text-decoration-color: color-mix(in srgb, var(--diff-ins-text-color) 10%, var(--foreground-point));

	--del-text-background-color: color-mix(in srgb, var(--del-text-color) 5%, var(--background-point));
	--del-code-background-color: color-mix(in srgb, var(--del-text-color) 15%, var(--background-point));
	--del-text-decoration-color: color-mix(in srgb, var(--del-text-color) 10%, var(--foreground-point));
	--diff-del-text-background-color: color-mix(in srgb, var(--diff-del-text-color) 5%, var(--background-point));
	--diff-del-code-background-color: color-mix(in srgb, var(--diff-del-text-color) 15%, var(--background-point));
	--diff-del-text-decoration-color: color-mix(in srgb, var(--diff-del-text-color) 10%, var(--foreground-point));
}

@media print {
	.pagebreak { break-after: always }
}

ins .wording-section .highlight:not(.idl) { background: var(--ins-code-background-color); }
diff-ins .wording-section .highlight:not(.idl) { background: var(--diff-ins-code-background-color); }
del .wording-section .highlight:not(.idl) { background: var(--del-code-background-color); }
diff-del .wording-section .highlight:not(.idl) { background: var(--diff-del-code-background-color); }


.tg  {
	border-collapse: collapse;
	border-spacing:0;
}

.tg td{
	padding:10px 10px;
	border-style: solid;
	border-width:1px;
	overflow: hidden;
	word-break: normal;
	border-color: var(--table-border-color, unset);
}
.tg th{
	font-weight: normal;
	padding: 10px 10px;
	border-style: solid;
	border-width: 1px;
	overflow: hidden;
	word-break: normal;
	border-color: black;
}
.tg .tg-c3ow { 
	border-color: unset;
	text-align: center;
	vertical-align: top
}

.quote-ins, quote-ins, quote-ins p, quote-ins div, span.quote-ins, span.quote-ins * {
	border-color: var(--ins-text-border-color);
}

.ins, ins, ins p, ins div, span.ins, span.ins * {
	background-color: var(--ins-text-background-color);
	background: var(--ins-text-background-color);
	color: var(--ins-text-color);
	text-decoration: underline;
	text-decoration-color: var(--ins-text-decoration-color);
	border-color: var(--ins-text-decoration-color);
}

.diff-ins, diff-ins, diff-ins p, diff-ins div, span.diff-ins, span.diff-ins * {
	background-color: var(--diff-ins-text-background-color);
	background: var(--diff-ins-text-background-color);
	color: var(--diff-ins-text-color);
	text-decoration: underline double;
	text-decoration-color: var(--diff-ins-text-decoration-color);
}

.del, del, del p, del div, span.del, span.del * {
	background-color: var(--del-text-background-color);
	background: var(--del-text-background-color);
	color: var(--del-text-color);
	text-decoration: line-through;
	text-decoration-color: var(--del-text-decoration-color);
}

.diff-del, diff-del, diff-del p, diff-del div, span.diff-del, span.diff-del * {
	background-color: var(--diff-del-text-background-color);
	background: var(--diff-del-text-background-color);
	color: var(--diff-del-text-color);
	text-decoration: line-through double;
	text-decoration-color: var(--diff-del-text-decoration-color);
}

code.c-kw {
	font-weight: bold;
}

math, span.math {
	font-family: serif;
	font-style: italic;
}

ul {
	list-style-type: "— ";
}

.wording-clause {
	counter-reset: wording-paragraph;
}

.wording-clause-header {
	font-size: 115%;
	display: block;
	padding-bottom: 1em;
	clear: both;
}

.wording-clause-number {
	font-weight: bold;
}

.wording-clause-title {
	font-weight: bold;
	margin: 2em;
}

.wording-clause-stable-tag {
	float: right;
}

.wording-clause-section-title {
	font-size: 105%;
	font-weight: bold;
}

.clause-stable-tag {
	float: right;
}

.footnote-ref {
	font-size: 75%;
	vertical-align: super;
}

.footnote {
	font-size: 75%;
	vertical-align: bottom;
}

table.invis, table.printf-specifiers {
	padding: 15px;
	border: 0px;
	tr {
		border: 0px;
	}
	th {
		width: 13%;
		border: 0px;
	}
	th ~ th {
		width:initial;
		border: 0px;
	}
	td {
		border: 0px;
	}
}

div.wording-section {
	counter-reset: wording-paragraph;
}

div.wording-numbered, div.wording-newnumbered {
	margin-left: 2.5em;
	margin-top: 1em;
	margin-bottom: 1em;
}

div.wording-numbered:before, div.wording-newnumbered:before {
	position: absolute;
	margin-left: -2.5em;
	display: block;
}

div.wording-numbered:before {
	content: counter(wording-paragraph);
	counter-increment: wording-paragraph;
	font-size: smaller;
}

div.wording-newnumbered:before {
	content: counter(wording-paragraph)"✨";
	counter-increment: wording-paragraph;
	font-size: smaller;
}

div.wording-numbered-list ul, div.wording-newnumbered ul {
	counter-reset: wording-list-item;
}

div.wording-numbered-list li, div.wording-newnumbered li {
	margin-left: 4em;
}

div.wording-numbered-list li:before, div.wording-newnumbered li:before {
	position: absolute;
	margin-left: -4em;
	display: block;
}

div.wording-numbered-list li:before {
	font-size: smaller;
	content: "(" counter(wording-paragraph) "." counter(wording-list-item) ")";
	counter-increment: wording-list-item;
}

div.wording-newnumbered-list li:before {
	content: "(✨" counter(wording-paragraph) "." counter(wording-list-item) ")";
	counter-increment: wording-list-item;
}

div.wording-numbered-0 {
	counter-reset: wording-paragraph -1;
}

div.wording-numbered-1 {
	counter-reset: wording-paragraph 0;
}

div.wording-numbered-2 {
	counter-reset: wording-paragraph 1;
}

div.wording-numbered-3 {
	counter-reset: wording-paragraph 2;
}

div.wording-numbered-4 {
	counter-reset: wording-paragraph 3;
}

div.wording-numbered-5 {
	counter-reset: wording-paragraph 4;
}

div.wording-numbered-6 {
	counter-reset: wording-paragraph 5;
}

div.wording-numbered-7 {
	counter-reset: wording-paragraph 6;
}

div.wording-numbered-8 {
	counter-reset: wording-paragraph 7;
}

div.wording-numbered-9 {
	counter-reset: wording-paragraph 8;
}

div.wording-numbered-10 {
	counter-reset: wording-paragraph 9;
}

div.wording-numbered-11 {
	counter-reset: wording-paragraph 10;
}

div.wording-numbered-12 {
	counter-reset: wording-paragraph 11;
}

div.wording-numbered-13 {
	counter-reset: wording-paragraph 12;
}

div.wording-numbered-14 {
	counter-reset: wording-paragraph 13;
}

div.wording-numbered-15 {
	counter-reset: wording-paragraph 14;
}

div.wording-numbered-16 {
	counter-reset: wording-paragraph 15;
}

div.wording-numbered-17 {
	counter-reset: wording-paragraph 16;
}

div.wording-numbered-18 {
	counter-reset: wording-paragraph 17;
}

div.wording-numbered-19 {
	counter-reset: wording-paragraph 18;
}

div.wording-numbered-20 {
	counter-reset: wording-paragraph 19;
}

div.wording-numbered-21 {
	counter-reset: wording-paragraph 20;
}

div.wording-numbered-22 {
	counter-reset: wording-paragraph 21;
}

div.wording-numbered-23 {
	counter-reset: wording-paragraph 22;
}

div.wording-numbered-24 {
	counter-reset: wording-paragraph 23;
}

div.wording-numbered-25 {
	counter-reset: wording-paragraph 24;
}

div.wording-numbered-25 {
	counter-reset: wording-paragraph 24;
}

div.wording-numbered-25 {
	counter-reset: wording-paragraph 24;
}

div.wording-numbered-25 {
	counter-reset: wording-paragraph 24;
}

div.wording-numbered-30 {
	counter-reset: wording-paragraph 29;
}

div.wording-numbered-31 {
	counter-reset: wording-paragraph 30;
}

div.wording-numbered-32 {
	counter-reset: wording-paragraph 31;
}

div.wording-numbered-33 {
	counter-reset: wording-paragraph 32;
}

div.wording-numbered-34 {
	counter-reset: wording-paragraph 33;
}

div.wording-numbered-35 {
	counter-reset: wording-paragraph 34;
}

div.wording-numbered-36 {
	counter-reset: wording-paragraph 35;
}

div.wording-numbered-37 {
	counter-reset: wording-paragraph 36;
}

div.wording-numbered-38 {
	counter-reset: wording-paragraph 37;
}

div.wording-numbered-39 {
	counter-reset: wording-paragraph 38;
}
</style>
<style>/* Boilerplate: style-autolinks */
.css.css, .property.property, .descriptor.descriptor {
    color: var(--a-normal-text);
    font-size: inherit;
    font-family: inherit;
}
.css::before, .property::before, .descriptor::before {
    content: "‘";
}
.css::after, .property::after, .descriptor::after {
    content: "’";
}
.property, .descriptor {
    /* Don't wrap property and descriptor names */
    white-space: nowrap;
}
.type { /* CSS value <type> */
    font-style: italic;
}
pre .property::before, pre .property::after {
    content: "";
}
[data-link-type="property"]::before,
[data-link-type="propdesc"]::before,
[data-link-type="descriptor"]::before,
[data-link-type="value"]::before,
[data-link-type="function"]::before,
[data-link-type="at-rule"]::before,
[data-link-type="selector"]::before,
[data-link-type="maybe"]::before {
    content: "‘";
}
[data-link-type="property"]::after,
[data-link-type="propdesc"]::after,
[data-link-type="descriptor"]::after,
[data-link-type="value"]::after,
[data-link-type="function"]::after,
[data-link-type="at-rule"]::after,
[data-link-type="selector"]::after,
[data-link-type="maybe"]::after {
    content: "’";
}

[data-link-type].production::before,
[data-link-type].production::after,
.prod [data-link-type]::before,
.prod [data-link-type]::after {
    content: "";
}

[data-link-type=element],
[data-link-type=element-attr] {
    font-family: Menlo, Consolas, "DejaVu Sans Mono", monospace;
    font-size: .9em;
}
[data-link-type=element]::before { content: "<" }
[data-link-type=element]::after  { content: ">" }

[data-link-type=biblio] {
    white-space: pre;
}

@media (prefers-color-scheme: dark) {
    :root {
        --selflink-text: black;
        --selflink-bg: silver;
        --selflink-hover-text: white;
    }
}
</style>
<style>/* Boilerplate: style-colors */
/* Any --*-text not paired with a --*-bg is assumed to have a transparent bg */
:root {
    color-scheme: light dark;

    --text: black;
    --bg: white;

    --unofficial-watermark: url(https://www.w3.org/StyleSheets/TR/2016/logos/UD-watermark);

    --logo-bg: #1a5e9a;
    --logo-active-bg: #c00;
    --logo-text: white;

    --tocnav-normal-text: #707070;
    --tocnav-normal-bg: var(--bg);
    --tocnav-hover-text: var(--tocnav-normal-text);
    --tocnav-hover-bg: #f8f8f8;
    --tocnav-active-text: #c00;
    --tocnav-active-bg: var(--tocnav-normal-bg);

    --tocsidebar-text: var(--text);
    --tocsidebar-bg: #f7f8f9;
    --tocsidebar-shadow: rgba(0,0,0,.1);
    --tocsidebar-heading-text: hsla(203,20%,40%,.7);

    --toclink-text: var(--text);
    --toclink-underline: #3980b5;
    --toclink-visited-text: var(--toclink-text);
    --toclink-visited-underline: #054572;

    --heading-text: #005a9c;

    --hr-text: var(--text);

    --algo-border: #def;

    --del-text: red;
    --del-bg: transparent;
    --ins-text: #080;
    --ins-bg: transparent;

    --a-normal-text: #034575;
    --a-normal-underline: #bbb;
    --a-visited-text: var(--a-normal-text);
    --a-visited-underline: #707070;
    --a-hover-bg: rgba(75%, 75%, 75%, .25);
    --a-active-text: #c00;
    --a-active-underline: #c00;

    --blockquote-border: silver;
    --blockquote-bg: transparent;
    --blockquote-text: currentcolor;

    --issue-border: #e05252;
    --issue-bg: #fbe9e9;
    --issue-text: var(--text);
    --issueheading-text: #831616;

    --example-border: #e0cb52;
    --example-bg: #fcfaee;
    --example-text: var(--text);
    --exampleheading-text: #574b0f;

    --note-border: #52e052;
    --note-bg: #e9fbe9;
    --note-text: var(--text);
    --noteheading-text: hsl(120, 70%, 30%);
    --notesummary-underline: silver;

    --assertion-border: #aaa;
    --assertion-bg: #eee;
    --assertion-text: black;

    --advisement-border: orange;
    --advisement-bg: #fec;
    --advisement-text: var(--text);
    --advisementheading-text: #b35f00;

    --warning-border: red;
    --warning-bg: hsla(40,100%,50%,0.95);
    --warning-text: var(--text);

    --amendment-border: #330099;
    --amendment-bg: #F5F0FF;
    --amendment-text: var(--text);
    --amendmentheading-text: #220066;

    --def-border: #8ccbf2;
    --def-bg: #def;
    --def-text: var(--text);
    --defrow-border: #bbd7e9;

    --datacell-border: silver;

    --indexinfo-text: #707070;

    --indextable-hover-text: black;
    --indextable-hover-bg: #f7f8f9;

    --outdatedspec-bg: rgba(0, 0, 0, .5);
    --outdatedspec-text: black;
    --outdated-bg: maroon;
    --outdated-text: white;
    --outdated-shadow: red;

    --editedrec-bg: darkorange;
}

@media (prefers-color-scheme: dark) {
    :root {
        --text: #ddd;
        --bg: black;

        --unofficial-watermark: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='400' height='400'%3E%3Cg fill='%23100808' transform='translate(200 200) rotate(-45) translate(-200 -200)' stroke='%23100808' stroke-width='3'%3E%3Ctext x='50%25' y='220' style='font: bold 70px sans-serif; text-anchor: middle; letter-spacing: 6px;'%3EUNOFFICIAL%3C/text%3E%3Ctext x='50%25' y='305' style='font: bold 70px sans-serif; text-anchor: middle; letter-spacing: 6px;'%3EDRAFT%3C/text%3E%3C/g%3E%3C/svg%3E");

        --logo-bg: #1a5e9a;
        --logo-active-bg: #c00;
        --logo-text: white;

        --tocnav-normal-text: #999;
        --tocnav-normal-bg: var(--bg);
        --tocnav-hover-text: var(--tocnav-normal-text);
        --tocnav-hover-bg: #080808;
        --tocnav-active-text: #f44;
        --tocnav-active-bg: var(--tocnav-normal-bg);

        --tocsidebar-text: var(--text);
        --tocsidebar-bg: #080808;
        --tocsidebar-shadow: rgba(255,255,255,.1);
        --tocsidebar-heading-text: hsla(203,20%,40%,.7);

        --toclink-text: var(--text);
        --toclink-underline: #6af;
        --toclink-visited-text: var(--toclink-text);
        --toclink-visited-underline: #054572;

        --heading-text: #8af;

        --hr-text: var(--text);

        --algo-border: #456;

        --del-text: #f44;
        --del-bg: transparent;
        --ins-text: #4a4;
        --ins-bg: transparent;

        --a-normal-text: #6af;
        --a-normal-underline: #555;
        --a-visited-text: var(--a-normal-text);
        --a-visited-underline: var(--a-normal-underline);
        --a-hover-bg: rgba(25%, 25%, 25%, .2);
        --a-active-text: #f44;
        --a-active-underline: var(--a-active-text);

        --borderedblock-bg: rgba(255, 255, 255, .05);

        --blockquote-border: silver;
        --blockquote-bg: var(--borderedblock-bg);
        --blockquote-text: currentcolor;

        --issue-border: #e05252;
        --issue-bg: var(--borderedblock-bg);
        --issue-text: var(--text);
        --issueheading-text: hsl(0deg, 70%, 70%);

        --example-border: hsl(50deg, 90%, 60%);
        --example-bg: var(--borderedblock-bg);
        --example-text: var(--text);
        --exampleheading-text: hsl(50deg, 70%, 70%);

        --note-border: hsl(120deg, 100%, 35%);
        --note-bg: var(--borderedblock-bg);
        --note-text: var(--text);
        --noteheading-text: hsl(120, 70%, 70%);
        --notesummary-underline: silver;

        --assertion-border: #444;
        --assertion-bg: var(--borderedblock-bg);
        --assertion-text: var(--text);

        --advisement-border: orange;
        --advisement-bg: #222218;
        --advisement-text: var(--text);
        --advisementheading-text: #f84;

        --warning-border: red;
        --warning-bg: hsla(40,100%,20%,0.95);
        --warning-text: var(--text);

        --amendment-border: #330099;
        --amendment-bg: #080010;
        --amendment-text: var(--text);
        --amendmentheading-text: #cc00ff;

        --def-border: #8ccbf2;
        --def-bg: #080818;
        --def-text: var(--text);
        --defrow-border: #136;

        --datacell-border: silver;

        --indexinfo-text: #aaa;

        --indextable-hover-text: var(--text);
        --indextable-hover-bg: #181818;

        --outdatedspec-bg: rgba(255, 255, 255, .5);
        --outdatedspec-text: black;
        --outdated-bg: maroon;
        --outdated-text: white;
        --outdated-shadow: red;

        --editedrec-bg: darkorange;
    }
    /* In case a transparent-bg image doesn't expect to be on a dark bg,
       which is quite common in practice... */
    img { background: white; }
}
</style>
<style>/* Boilerplate: style-counters */
body {
    counter-reset: example figure issue;
}
.issue {
    counter-increment: issue;
}
.issue:not(.no-marker)::before {
    content: "Issue " counter(issue);
}

.example {
    counter-increment: example;
}
.example:not(.no-marker)::before {
    content: "Example " counter(example);
}
.invalid.example:not(.no-marker)::before,
.illegal.example:not(.no-marker)::before {
    content: "Invalid Example" counter(example);
}

figcaption {
    counter-increment: figure;
}
figcaption:not(.no-marker)::before {
    content: "Figure " counter(figure) " ";
}
</style>
<style>/* Boilerplate: style-issues */
a[href].issue-return {
    float: right;
    float: inline-end;
    color: var(--issueheading-text);
    font-weight: bold;
    text-decoration: none;
}
</style>
<style>/* Boilerplate: style-md-lists */
/* This is a weird hack for me not yet following the commonmark spec
   regarding paragraph and lists. */
[data-md] > :first-child {
    margin-top: 0;
}
[data-md] > :last-child {
    margin-bottom: 0;
}
</style>
<style>/* Boilerplate: style-selflinks */
:root {
    --selflink-text: white;
    --selflink-bg: gray;
    --selflink-hover-text: black;
}
.heading, .issue, .note, .example, li, dt {
    position: relative;
}
a.self-link {
    position: absolute;
    top: 0;
    left: calc(-1 * (3.5rem - 26px));
    width: calc(3.5rem - 26px);
    height: 2em;
    text-align: center;
    border: none;
    transition: opacity .2s;
    opacity: .5;
}
a.self-link:hover {
    opacity: 1;
}
.heading > a.self-link {
    font-size: 83%;
}
.example > a.self-link,
.note > a.self-link,
.issue > a.self-link {
    /* These blocks are overflow:auto, so positioning outside
       doesn't work. */
    left: auto;
    right: 0;
}
li > a.self-link {
    left: calc(-1 * (3.5rem - 26px) - 2em);
}
dfn > a.self-link {
    top: auto;
    left: auto;
    opacity: 0;
    width: 1.5em;
    height: 1.5em;
    background: var(--selflink-bg);
    color: var(--selflink-text);
    font-style: normal;
    transition: opacity .2s, background-color .2s, color .2s;
}
dfn:hover > a.self-link {
    opacity: 1;
}
dfn > a.self-link:hover {
    color: var(--selflink-hover-text);
}

a.self-link::before            { content: "¶"; }
.heading > a.self-link::before { content: "§"; }
dfn > a.self-link::before      { content: "#"; }
</style>
<style>/* Boilerplate: style-syntax-highlighting */
code.highlight { padding: .1em; border-radius: .3em; }
pre.highlight, pre > code.highlight { display: block; padding: 1em; margin: .5em 0; overflow: auto; border-radius: 0; }

.highlight:not(.idl) { background: rgba(0, 0, 0, .03); }
c-[a] { color: #990055 } /* Keyword.Declaration */
c-[b] { color: #990055 } /* Keyword.Type */
c-[c] { color: #708090 } /* Comment */
c-[d] { color: #708090 } /* Comment.Multiline */
c-[e] { color: #0077aa } /* Name.Attribute */
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   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P3540R2<br><code class="highlight"><c- cp>#embed</c-></code> offset parameter</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="profile-and-date"><span class="content">Published Proposal, <time class="dt-updated" datetime="2025-06-05">2025-06-05</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt class="editor">Authors:
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:phdofthehouse@gmail.com">JeanHeyd Meneide</a>
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:shepherd@soasis.org">Shepherd (Shepherd's Oasis LLC)</a>
     <dt>Latest:
     <dd><a href="https://thephd.dev/_vendor/future_cxx/papers/d3540.html">https://thephd.dev/_vendor/future_cxx/papers/d3540.html</a>
     <dt>Paper Source:
     <dd><a href="https://github.com/ThePhD/future_cxx/blob/main/papers/source/d3540.bs">GitHub ThePhD/future_cxx</a>
     <dt>Implementation:
     <dd><a href="https://github.com/ThePhD/embed">GitHub ThePhD/embed</a>
     <dt>Project:
     <dd>ISO/IEC 14882 Programming Languages — C++, ISO/IEC JTC1/SC22/WG21
     <dt>Audience:
     <dd>EWG
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>An additional, user-supported embed parameter implemented in Clang and GCC for providing an offset.</p>
  </div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li>
     <a href="#changelog"><span class="secno">1</span> <span class="content">Changelog</span></a>
     <ol class="toc">
      <li><a href="#changelog-r2"><span class="secno">1.1</span> <span class="content">Revision 2 - June <sup>5th</sup>, 2025</span></a>
      <li><a href="#changelog-r1"><span class="secno">1.2</span> <span class="content">Revision 1 - February 14<sup>th</sup>, 2025</span></a>
      <li><a href="#changelog-r0"><span class="secno">1.3</span> <span class="content">Revision 0 - December 13<sup>th</sup>, 2024</span></a>
     </ol>
    <li><a href="#intro"><span class="secno">2</span> <span class="content">Introduction and Motivation</span></a>
    <li><a href="#design"><span class="secno">3</span> <span class="content">Design</span></a>
    <li>
     <a href="#wording"><span class="secno">4</span> <span class="content">Wording</span></a>
     <ol class="toc">
      <li><a href="#wording-intent"><span class="secno">4.1</span> <span class="content">Intent</span></a>
      <li>
       <a href="#wording-specification"><span class="secno">4.2</span> <span class="content">Proposed Language Wording</span></a>
       <ol class="toc">
        <li><a href="#wording-specification-cpp.pre"><span class="secno">4.2.1</span> <span class="content">Add to the <em>control-line</em> production in §15.1 Preamble [<strong>cpp.pre</strong>] a new grammar production for <code class="highlight"><c- n>offset</c-></code></span></a>
        <li><a href="#wording-specification-cpp.embed.param.offset"><span class="secno">4.2.2</span> <span class="content">Add a new sub-clause §15.4.2.✨ under Resource Inclusion for Embed parameters for the new <code class="highlight"><c- n>offset</c-></code> parameter [<strong>cpp.embed.param.offset</strong>]</span></a>
       </ol>
      <li><a href="#wording-specification-if_empty.example"><span class="secno">4.3</span> <span class="content">Add a new example to the <code class="highlight"><c- n>if_empty</c-></code> embed parameter [cpp.embed.if.empty] section</span></a>
     </ol>
   </ol>
  </nav>
  <main>
<script>
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   <script async id="MathJax-script" src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-chtml.js"></script>
   <div class="pagebreak"></div>
   <h2 class="heading settled" data-level="1" id="changelog"><span class="secno">1. </span><span class="content">Changelog</span><a class="self-link" href="#changelog"></a></h2>
   <h3 class="heading settled" data-level="1.1" id="changelog-r2"><span class="secno">1.1. </span><span class="content">Revision 2 - June <sup>5th</sup>, 2025</span><a class="self-link" href="#changelog-r2"></a></h3>
   <ul>
    <li data-md>
     <p>Design was expanded upon in Revision 1 and further explicated in this version to prevent people from being confused about what is being proposed here and what the specification was asking for. It was not recorded in the previous changelog: it is being recorded here.</p>
    <li data-md>
     <p>Revision 2 does not add or change any of the wording in a way that matters; it just fixes clerical errors, typos, and aligns dates.</p>
    <li data-md>
     <p>One such typo: fixes "It shall provide" to "It provides", as the "shall" is spurious in C++ wording since it does not provide anything.</p>
    <li data-md>
     <p><a href="#design">§ 3 Design</a> elaborates that this is meant to be that <code class="highlight"><c- n>offset</c-></code> applies before <code class="highlight"><c- n>limit</c-></code> is applied, as what is implemented in <code class="highlight"><c- n>clang</c-><c- o>::</c-><c- n>offset</c-></code> and <code class="highlight"><c- n>gnu</c-><c- o>::</c-><c- n>offset</c-></code> today.</p>
    <li data-md>
     <p>Some discussion during an SG22 meeting about restricting the order of embed parameters. This isn’t present in any implementation or in the C wording, and it’s an awful experience overall: rejected this design to proceed forward.</p>
   </ul>
   <h3 class="heading settled" data-level="1.2" id="changelog-r1"><span class="secno">1.2. </span><span class="content">Revision 1 - February 14<sup>th</sup>, 2025</span><a class="self-link" href="#changelog-r1"></a></h3>
   <ul>
    <li data-md>
     <p>Minor typo and wording cleanup.</p>
   </ul>
   <h3 class="heading settled" data-level="1.3" id="changelog-r0"><span class="secno">1.3. </span><span class="content">Revision 0 - December 13<sup>th</sup>, 2024</span><a class="self-link" href="#changelog-r0"></a></h3>
   <ul>
    <li data-md>
     <p>Initial release.</p>
   </ul>
   <h2 class="heading settled" data-level="2" id="intro"><span class="secno">2. </span><span class="content">Introduction and Motivation</span><a class="self-link" href="#intro"></a></h2>
   <p>The goal is to add the extremely-popular and already-implemented <code class="highlight"><c- n>gnu</c-><c- o>::</c-><c- n>offset</c-></code> and <code class="highlight"><c- n>clang</c-><c- o>::</c-><c- n>offset</c-></code> parameters as standard parameters. That is the only motivation of this proposal; to standardize existing practice.</p>
   <p>Originally, users asked to add this parameter, but only after C23 standardized. Given the late stage that users have asked -- waiting until the very end -- it has to be added separately. This proposal aims to standardize what users have asked for, and what Clang and GCC have implemented.</p>
   <h2 class="heading settled" data-level="3" id="design"><span class="secno">3. </span><span class="content">Design</span><a class="self-link" href="#design"></a></h2>
   <p>The design of <code class="highlight"><c- n>offset</c-><c- p>(</c-><c- n>some</c-><c- o>-</c-><c- n>preprocessor</c-><c- o>-</c-><c- n>constant</c-><c- o>-</c-><c- n>value</c-><c- p>)</c-></code> is straightforward:</p>
   <ul>
    <li data-md>
     <p><code class="highlight"><c- n>offset</c-></code> discards <code class="highlight"><c- n>some</c-><c- o>-</c-><c- n>preprocessor</c-><c- o>-</c-><c- n>constant</c-><c- o>-</c-><c- n>value</c-></code> items, up to the full size of the resource;</p>
    <li data-md>
     <p>nothing happens if <code class="highlight"><c- n>some</c-><c- o>-</c-><c- n>preprocessor</c-><c- o>-</c-><c- n>constant</c-><c- o>-</c-><c- n>value</c-></code> evaluates to <code class="highlight"><c- mi>0</c-></code>;</p>
    <li data-md>
     <p>if <code class="highlight"><c- n>offset</c-></code> is greater than or equal to the size of the resource, the resource is considered empty;</p>
    <li data-md>
     <p><code class="highlight"><c- n>limit</c-></code> does not shrink the file to a given size before <code class="highlight"><c- n>offset</c-></code>; <code class="highlight"><c- n>offset</c-></code> is applied to the original file size (called the "implementation-resource-count" in the wording).</p>
   </ul>
   <p>These are the only tenets of the design, and match the practice for existing implementations <code class="highlight"><c- n>gnu</c-><c- o>::</c-><c- n>offset</c-></code> and <code class="highlight"><c- n>clang</c-><c- o>::</c-><c- n>offset</c-></code>. It is also how the original author envisioned this when it was first PR’d to Clang, and the original tests (plus new ones) still pass in the LLVM/clang and gnu/gcc repositories.</p>
   <p>There was some discussion during the June 4<sup>th</sup>, 2025 about the order of parameters. This turned into a significant enough change that it is a separate paper. No additional discussion or changes are proposed for this paper: it is exactly a standardization of existing practice and what was approved in Austria.</p>
   <h2 class="heading settled" data-level="4" id="wording"><span class="secno">4. </span><span class="content">Wording</span><a class="self-link" href="#wording"></a></h2>
   <p>This wording is relative to C++'s latest working draft.</p>
   <h3 class="heading settled" data-level="4.1" id="wording-intent"><span class="secno">4.1. </span><span class="content">Intent</span><a class="self-link" href="#wording-intent"></a></h3>
   <p>The intent of the wording is to provide a preprocessing directive that:</p>
   <ul>
    <li data-md>
     <p>allows an <code class="highlight"><c- n>offset</c-></code> parameter skipping over a number of elements before beginning to write out elements to the comma-delimited list;</p>
    <li data-md>
     <p>and, applies to the actual size of the resource (and not to any applied <code class="highlight"><c- n>limit</c-></code>).</p>
   </ul>
   <h3 class="heading settled" data-level="4.2" id="wording-specification"><span class="secno">4.2. </span><span class="content">Proposed Language Wording</span><a class="self-link" href="#wording-specification"></a></h3>
   <h4 class="heading settled" data-level="4.2.1" id="wording-specification-cpp.pre"><span class="secno">4.2.1. </span><span class="content">Add to the <em>control-line</em> production in §15.1 Preamble [<strong>cpp.pre</strong>] a new grammar production for <code class="highlight"><c- n>offset</c-></code></span><a class="self-link" href="#wording-specification-cpp.pre"></a></h4>
   <blockquote>
    <div class="wording-section">
     <div>
      <p><em>embed-standard-parameter</em>:</p>
      <dl>
       <dd data-md>
        <p><strong>limit</strong> <strong>(</strong> <em>pp-balanced-token-seq</em> <strong>)</strong></p>
       <dd data-md>
        <ins><strong>offset</strong> <strong>(</strong> <em>pp-balanced-token-seq</em> <strong>)</strong></ins>
       <dd data-md>
        <p><strong>prefix</strong> <strong>(</strong> <em>pp-balanced-token-seq</em><sub><em>opt</em></sub> <strong>)</strong></p>
       <dd data-md>
        <p><strong>suffix</strong> <strong>(</strong> <em>pp-balanced-token-seq</em><sub><em>opt</em></sub> <strong>)</strong></p>
       <dd data-md>
        <p><strong>if_empty</strong> <strong>(</strong> <em>pp-balanced-token-seq</em><sub><em>opt</em></sub> <strong>)</strong></p>
      </dl>
     </div>
    </div>
   </blockquote>
   <h4 class="heading settled" data-level="4.2.2" id="wording-specification-cpp.embed.param.offset"><span class="secno">4.2.2. </span><span class="content">Add a new sub-clause §15.4.2.✨ under Resource Inclusion for Embed parameters for the new <code class="highlight"><c- n>offset</c-></code> parameter [<strong>cpp.embed.param.offset</strong>]</span><a class="self-link" href="#wording-specification-cpp.embed.param.offset"></a></h4>
   <blockquote class="quote-ins">
    <ins>
     <div class="wording-section" id="cpp.embed.param.offset">
      <div class="wording-section-header"> <span class="wording-clause-number">15.4.2.✨</span> <span class="wording-clause-title"><code class="highlight"><c- n>offset</c-></code> parameter</span> <span class="wording-clause-stable-tag">[<b>cpp.embed.param.offset</b>]</span> </div>
      <div class="wording-numbered">
       <p>An <em>embed-parameter</em> of the form <code class="highlight"><c- n>offset</c-> <c- p>(</c-> <em><c- n>pp</c-><c- o>-</c-><c- n>balanced</c-><c- o>-</c-><c- n>token</c-><c- o>-</c-><c- n>seq</c-></em> <c- p>)</c-></code> denotes the number of elements to be skipped from the resource. It shall appear at most once in the <em>embed-parameter-seq</em>.</p>
      </div>
      <div class="wording-numbered">
       <p>The <em>pp-balanced-token-seq</em> is evaluated as a <em>constant-expression</em> using the rules as described in conditional inclusion ([<a href="http://eel.is/c++draft/cpp.cond">cpp.cond</a>]), but without being processed as in normal text an additional time.</p>
      </div>
      <div class="wording-numbered">
       <p>The <em>constant-expression</em> shall be an integral constant expression whose value is greater than or equal to zero. It provides the value for <em>resource-offset</em>. The embed directive performs resource-offset consecutive calls to <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>fgetc</c-></code> ([<a href="http://eel.is/c++draft/cstdio.syn">cstdio.syn</a>]) from the resource, as a binary file. If a call to <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>fgetc</c-></code> returns <code class="highlight"><c- n>EOF</c-></code>, the resouce is considered empty. Otherwise, the result of the call is discarded. The resource-count is changed to be</p>
       <ul>
        <li data-md>
         <p>the value is computed using the <code class="highlight"><c- n>limit</c-></code> <em>embed-parameter</em> ([<a href="https://thephd.dev/_vendor/future_cxx/papers/d1967.html#cpp.embed.param.limit">cpp.embed.param.limit</a>]), if the <code class="highlight"><c- n>limit</c-></code> <em>embed-parameter</em> is present. Let the value computed by the <code class="highlight"><c- n>limit</c-></code> <em>embed-parameter</em> be <em>limit-value</em>. resource-count becomes $max(min(\text{limit-value}, \text{implementation-resource-count} - \text{resource-offset}), 0)$.</p>
        <li data-md>
         <p>Otherwise, $max(\text{implementation-resource-count} - \text{resource-offset}, 0)$.</p>
       </ul>
      </div>
      <p>[<em>Example</em>:</p>
<pre class="language-cpp highlight"><c- k>constexpr</c-> <c- k>const</c-> <c- b>unsigned</c-> <c- b>char</c-> <c- n>sound_signature</c-><c- p>[]</c-> <c- o>=</c-> <c- p>{</c->
  <c- c1>// a hypothetical resource capable of expanding to four or more elements</c->
<c- cp>#embed &lt;sdk/jump.wav> limit(2+2)</c->
<c- p>};</c->

<c- k>constexpr</c-> <c- k>const</c-> <c- b>unsigned</c-> <c- b>char</c-> <c- n>truncated_sound_signature</c-><c- p>[]</c-> <c- o>=</c-> <c- p>{</c->
  <c- c1>// the same hypothetical resource capable of expanding to four or more elements</c->
<c- cp>#embed &lt;sdk/jump.wav> offset(2) limit(2)</c->
<c- p>};</c->

<c- k>static_assert</c-><c- p>(</c-><c- k>sizeof</c-><c- p>(</c-><c- n>sound_signature</c-><c- p>)</c-> <c- o>==</c-> <c- mi>4</c-><c- p>);</c->
<c- k>static_assert</c-><c- p>(</c-><c- k>sizeof</c-><c- p>(</c-><c- n>truncated_sound_signature</c-><c- p>)</c-> <c- o>==</c-> <c- mi>2</c-><c- p>);</c->
<c- k>static_assert</c-><c- p>(</c-><c- n>sound_signature</c-><c- p>[</c-><c- mi>2</c-><c- p>]</c-> <c- o>==</c-> <c- n>truncated_sound_signature</c-><c- p>[</c-><c- mi>0</c-><c- p>]);</c->
<c- k>static_assert</c-><c- p>(</c-><c- n>sound_signature</c-><c- p>[</c-><c- mi>3</c-><c- p>]</c-> <c- o>==</c-> <c- n>truncated_sound_signature</c-><c- p>[</c-><c- mi>1</c-><c- p>]);</c->
</pre>
      <p>– <em>end example</em>]</p>
     </div>
    </ins>
   </blockquote>
   <h3 class="heading settled" data-level="4.3" id="wording-specification-if_empty.example"><span class="secno">4.3. </span><span class="content">Add a new example to the <code class="highlight"><c- n>if_empty</c-></code> embed parameter [cpp.embed.if.empty] section</span><a class="self-link" href="#wording-specification-if_empty.example"></a></h3>
   <blockquote class="quote-ins">
    <ins>
     <p>[<em>Example</em>: Given a resource <code class="highlight"><c- o>&lt;</c-><c- n>single_byte</c-><c- o>></c-></code> that has an implementation-resource-count of 1, the following directives:</p>
<pre class="language-cpp highlight"><c- cp>#embed &lt;single_byte> offset(1) if_empty(44203)</c->
<c- cp>#embed &lt;single_byte> limit(0)  offset(1) if_empty(44203)</c->
</pre>
     <p>are replaced with:</p>
<pre class="language-cpp highlight"><c- mi>42203</c->
<c- mi>42203</c->
</pre>
     <p>– <em>end example</em>]</p>
     <p>[<em>Example</em>: Given a resource <code class="highlight"><c- o>&lt;</c-><c- n>single_byte</c-><c- o>></c-></code> that has an implementation-resource-count of 1, <code class="highlight"><c- n>__has_embed</c-></code> will be considered empty despite <code class="highlight"><c- n>limit</c-><c- p>(</c-><c- mi>1</c-><c- p>)</c-></code>, as <code class="highlight"><c- n>offset</c-><c- p>(</c-><c- mi>1</c-><c- p>)</c-></code> has exhausted the implementation-resource-count:</p>
<pre class="language-cpp highlight"><c- b>int</c-> <c- nf>infinity_zero</c-> <c- p>()</c-> <c- p>{</c->
<c- cp>#if __has_embed(&lt;single_byte> limit(1) offset(1) prefix(some tokens)) == __STDC_EMBED_EMPTY__</c->
  <c- c1>// if &lt;single_byte> exists, this</c->
  <c- c1>// conditional inclusion branch is taken and the function</c->
  <c- c1>// returns 0.</c->
  <c- k>return</c-> <c- mi>0</c-><c- p>;</c->
<c- cp>#else</c->
  <c- c1>// otherwise, the resource does not exist</c->
<c- cp>#error "The resource does not exist"</c->
<c- cp>#endif</c->
<c- p>}</c->
</pre>
     <p>– <em>end example</em>]</p>
    </ins>
   </blockquote>
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